1. Field of the Invention
The invention relates to electromagnetic working of materials, and more particularly it relates to a method of electromagnetic working of materials.
The invention can be utilized for dispersing, emulsifying and mixing suspensions, predominantly in the chemical and related industries.
2. Description of the Prior Art
There is known a method of electromagnetic working of materials (U.S. Pat. No. 3,219,318) residing in producing a variable magnetic field to induce chaotic motion of magnetic elements with the aim of working, e.g. dispersing or mixing, a material fed into the working zone, e.g. a suspension or emulsion.
The method is intended for working materials in relatively small receptacles or vessels, e.g. test tubes or laboratory glasses.
Devices capable of performing this method comprise an electric winding operable to generate a variable magnetic field in the working zone, and a working chamber of a non-magnetic material accommodating therein magnetic elements. The quantity of magnetic elements in the working chamber is selected so that in their motion they should be adequately spaced from one another and not subjected to frequent collisions and excessive wear incurred by such collisions.
This quantity of magnetic elements is short of their distribution in one layer over the entire area of the bottom of the chamber.
A shortcoming of this known method is its relatively low efficiency on account of incomplete utilization of the energy of the magnetic field in the working volume, caused by the relatively small quantity of the magnetic elements; another shortcoming is the specific productivity of the process declining and its efficiency decreasing with the dimensions of the working chamber and its volume being increased, with a sharp rise of the energy input, which prohibits the creation of high-efficiency units of adequate productivity and throughput.
There is known another method of electromagnetic working of materials (U.S. Pat. No. 3,987,967), which includes acting upon a material received in the working zone by magnetic elements moving chaotically under the action thereupon of a variable magnetic field, the elements being accommodated in the working zone in a layer of which the height is determined by the geometrical dimensions of the magnetic elements, their magnetic parameters and density, and also by the intensity and frequency of the magnetic field.
A shortcoming of this method of the prior art is inadequate quality of the working of materials in a continuous duty, relatively high energy inputs and insufficient intensity of the working process. This is caused by the fact that when the working of suspensions is conducted in a continuous process, a considerable part of the volume of the suspension passes either through or above the layer of magnetic elements without being adequately treated. The probability of such slipping-through of unworked suspension lowers with a growing height of the layer of magnetic elements accommodated in the working zone. However, the height of their layer in the working zone in the method of the prior art is relatively limited, and in practical implementations would not be made in excess of 20-30 cm on account of the growing moment of resistance to the motion of the magnetic elements caused by gravity forces; in other words, when magnetic elements are loaded into the working zone in a layer exceeding 20-30 cm, those of the magnetic elements which are close to the bottom of this layer would remain all but stationary and not take part in useful work.
Furthermore, the method of the prior art would not provide for monitoring and maintaining an optimized height of the layer of magnetic elements throughout the operation, as the process of the working of materials, and of abrasive suspensions and pastes in particular, is accompanied by the wearing away of the magnetic elements, with the products of such wear being carried away by the materials being worked, so that the mass and height of the layer of the magnetic elements in the working zone declines, and the efficiency and quality of the working operation declines correspondingly.